Hmm... The most glaringly bad things are:
1: Hard to tell where to go, or where you even CAN go.
2: The tanks of water that you cant even tell are full of water. I mean, if your gonna do that, you should use complete water blocks, not top and bottom only ones.
3: Random Ice Blocks scattered everywhere. I mean, why are there giant chunks of ice with pipes sticking out of them? The design doesn't even make sense. Plus, the textures on them are transparent, and that looks really horrible with those textures.
Best things about it:
1: The music. Where'd it come from? It was pretty cool, you just need to make it loop correctly, without fading.
2: The theme. It's really a nice idea, the ice factory thing, you just need to pull it off better.
3: The gimmicks in it, like the elevator, and the bridge, made it a lot more interesting.
Overall, I think it's not BAD, but it could use a lot of improvement. Keep up the good work!